Breathing exerciser



FIG. 1 is a front elevational view of a breathing exerciser showing my new design;

FIG. 2 is a right side elevational view thereof with the hose and mouthpiece cut away;

FIG. 3 is a bottom plan view thereof with the hose and mouthpiece cut away;

FIG. 4 is a top plan view thereof, with the hose and mouthpiece cut away;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a left side elevational view thereof with the hose and mouthpiece cut away;

FIG. 7 is a side elevational view of the mouthpiece thereof with the hose cut away; and

FIG. 8 is an end elevational view of the mouthpiece thereof. 

The ornamental design for a breathing exerciser, as shown. 